In late 2020, after circulating for almost a year in the human population, severe acute
respiratory syndrome coronavirus 2 (SARS-CoV-2) exhibited a major step change in its …

Importance Estimates of the rate of waning of vaccine effectiveness (VE) against COVID-19
are key to assess population levels of protection and future needs for booster doses to face …

The Omicron, or Pango lineage B. 1.1. 529, variant of severe acute respiratory syndrome
coronavirus 2 (SARS-CoV-2) carries multiple spike mutations with high transmissibility and …

Background The emergence of immune-escape variants of severe acute respiratory
syndrome coronavirus 2 warrants the use of sequence-adapted vaccines to provide …

Background The omicron variant (B. 1.1. 529) of SARS-CoV-2 has demonstrated partial
vaccine escape and high transmissibility, with early studies indicating lower severity of …

Convergent evolution of SARS-CoV-2 Omicron BA. 2, BA. 4, and BA. 5 lineages has led to
the emergence of several new subvariants, including BA. 2.75. 2, BA. 4.6. and BQ. 1.1. The …

The emergence of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) variants
in the Omicron lineage has resulted in diminished Coronavirus Disease 2019 (COVID-19) …

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) Omicron (B. 1.1. 529)
variant is highly transmissible with potential immune escape. We conducted a test-negative …

Background Few data exist on the comparative safety and immunogenicity of different
COVID-19 vaccines given as a third (booster) dose. To generate data to optimise selection …

Epidemiologic surveillance has revealed decoupling of Coronavirus Disease 2019 (COVID-
19) hospitalizations and deaths from case counts after emergence of the Omicron (B. 1.1 …